Work herein is proposed to prepare sufficient amounts of the chlorohydroxyadducts of polychlorinated biphenyls (PCB's). These chlorohydroxybiphenyls have been suggested to be the precursors that undergo ring closure to the very toxic chlorodibenzo-p-dioxins and chlorodibenzofurans. Several chlorohydroxybiphenyls have been made in a prototype of an electrochemical flow-thru cell. It is proposed to design and construct a more efficient electrochemical flow-thru cell, capable of being maintained at high temperature and pressure and being transparent to high intensity light. Using this efficient flow-thru cell, pure PCB isomers would be electrochemically oxidized and their primary hydrolysis products made. Isolation and purification of the products by preparative thin-layer or gas chromatography, vacuum sublimation or high-pressure column chromatography would follow. The conventional chemical synthesis routes produce low yields or a mixture of products. Isolation of the same metabolic hydrolysis products, although very important and of necessity, produce not only small amounts, but require long periods of time and usually large experimental testing stations. Electrochemical studies of hydroxylation reactions provide for more products at lower cost and in the process can suggest the reaction schemes for the degradation of persistent chemicals. Important parallels between electrochemical and metabolic or natural degradation schemes of these persistent chemicals can be made.